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authorad <ad@NetBSD.org>2008-03-11 00:40:38 +0000
committerad <ad@NetBSD.org>2008-03-11 00:40:38 +0000
commit3f5fa954a6dfd69ada1183753ebf877b9b7ac5c9 (patch)
tree3e86f3085c83b6235cde3bb66c82be44db30ea64 /sys
parentb714b9dd42cf04c90f6312f8afa2cf6a6c50c024 (diff)
tsc_get_timecount: remove unneeded instructions. Pointed out by dsl@.
Diffstat (limited to 'sys')
-rw-r--r--sys/arch/amd64/amd64/amd64func.S6
-rw-r--r--sys/arch/i386/i386/i386func.S8
2 files changed, 5 insertions, 9 deletions
diff --git a/sys/arch/amd64/amd64/amd64func.S b/sys/arch/amd64/amd64/amd64func.S
index 04e8b8faa1a..d07941285ba 100644
--- a/sys/arch/amd64/amd64/amd64func.S
+++ b/sys/arch/amd64/amd64/amd64func.S
@@ -1,4 +1,4 @@
-/* $NetBSD: amd64func.S,v 1.1 2008/03/10 22:03:40 ad Exp $ */
+/* $NetBSD: amd64func.S,v 1.2 2008/03/11 00:40:38 ad Exp $ */
/*-
* Copyright (c) 2008 The NetBSD Foundation, Inc.
@@ -56,9 +56,7 @@ ENTRY(tsc_get_timecount)
orl CC_DENOM+4(%rdi), %eax /* cc_denom > 0xffffffff) */
jnz 2f /* return tsc_slow_timecount() */
rdtsc /* cc = cpu_counter32(); */
- movl $0, %edx
- subl CC_CC(%rdi), %eax /* cc -= cc->cc_cc; */
- adcl $0, %edx /* if (cc < 0) cc += 0x100000000; */
+ subl CC_CC(%rdi), %eax /* cc -= cc->cc_cc; (can wrap) */
mull CC_DELTA(%rdi) /* rcc = (cc * ci->ci_cc.cc_delta) */
divl CC_DENOM(%rdi) /* / ci->ci_cc.cc_denom */
addl CC_VAL(%rdi), %eax /* + ci->ci_cc.cc_val; */
diff --git a/sys/arch/i386/i386/i386func.S b/sys/arch/i386/i386/i386func.S
index 4866c687300..74f26cd5257 100644
--- a/sys/arch/i386/i386/i386func.S
+++ b/sys/arch/i386/i386/i386func.S
@@ -1,4 +1,4 @@
-/* $NetBSD: i386func.S,v 1.5 2008/03/10 22:04:06 ad Exp $ */
+/* $NetBSD: i386func.S,v 1.6 2008/03/11 00:40:38 ad Exp $ */
/*-
* Copyright (c) 1998, 2007, 2008 The NetBSD Foundation, Inc.
@@ -43,7 +43,7 @@
*/
#include <machine/asm.h>
-__KERNEL_RCSID(0, "$NetBSD: i386func.S,v 1.5 2008/03/10 22:04:06 ad Exp $");
+__KERNEL_RCSID(0, "$NetBSD: i386func.S,v 1.6 2008/03/11 00:40:38 ad Exp $");
#include <machine/specialreg.h>
#include <machine/segments.h>
@@ -181,9 +181,7 @@ ENTRY(tsc_get_timecount)
orl CC_DENOM+4(%edi), %eax /* cc_denom > 0xffffffff) */
jnz 2f /* return tsc_slow_timecount() */
rdtsc /* cc = cpu_counter32(); */
- movl $0, %edx
- subl CC_CC(%edi), %eax /* cc -= cc->cc_cc; */
- adcl $0, %edx /* if (cc < 0) cc += 0x100000000; */
+ subl CC_CC(%edi), %eax /* cc -= cc->cc_cc; (can wrap) */
mull CC_DELTA(%edi) /* rcc = (cc * ci->ci_cc.cc_delta) */
divl CC_DENOM(%edi) /* / ci->ci_cc.cc_denom */
addl CC_VAL(%edi), %eax /* + ci->ci_cc.cc_val; */